Thermal relief valve.

[raygsmm]

Good day all,
We have a diesel tank ,there is portion of piping systm 95 m in length, It connects the tank to MOV .There is an isolation valve on the tank.That means the 95 piping is extend between the isolatin valve and the MOV(motor operated valve).Do we need relief valve to protect the pipe from the excess prssure that may result from liquid thermal expansion.?
Do we need to run thermal calculations?
Thanks

 

[IFRs]

I would put thermal relief around the valve but your environment might argue otherwise.

 

[Longinthetooth]

Some guidelines from a well known standard.

1. Does the pipeline run through public property.
2. Will an overpressure failure cause serious consequential damage.
3. Does the line run through a well populated site area.
4. Does the pipe carry a critical plant service.
Does the line contain valves or fittings whose reliability is of critical importance to the saferty of the plant.
5. Is the pipe inventory hazardous.
6. Is the line or any component brittle.

If the anwer to any of these is well, then overpressure must provided.

If the line is subject to ambient (eg solar) temperature increases of over 20C, then overpressure is a likely scenario.

 

[Longinthetooth]

Sorry, the statememt should read " If the answer to any of these is yes........"

 

[BigInch]

Add to that, "What does your design code say?"

Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso